Grate



May 16, 1933. D. A |TT| E 1,908,854

GRATE Filed Jan. 14, 1951 2 Sheets-Sheet l Patented May 16, 1933 UNITED Y STATES DAVID A. LITTLE, OF PHILADELPHIA, PENNSYLVAIA GRATE Application led January 14, 1931. Serial No. 508,737.

My invention relates to gratesl for stoves or furnaces in which small anthracite coal may be used as fuel.

The main purpose of my invention is to provide a grate for burning fine- `fuel withl a supplemental air-supplying section which can be used to adjustably break up the fuel bed and feed air within the body of the fuel bed at the points where the bed has been disturbed. A further purpose is to provide Va grate with two sets of bars movable under different laws of movement and each set having independent lever control mechanism.

A further purpose is to provide a grate bar construction for burning small anthracite coal which comprises two sets of bars, one set being pivoted to oscillate and the other set adapted to vertical movement to adjust the supply of air and to release it within the body of the lire bed.

A further purpose is to provide a grate that is easy to manufacture and to install and which at the same time well meets the needs of service.v

A further purpose is to provide special airadmitting grate-means which is useful also to remove ashes at the point of using.

Further purposes will appear'in the specification and in the claims.

I have elected to show one form only of the many different forms of my invention, selecting a form that is vpractical and efficient in operation and which well illustrates the principles involved.

Figure 1 is a vertical section of a furnace taken on a line which would correspond with line A-A of Figure 2 and showing a grate of that general character in place in a furnace.

Figure 2 is a top plan view of one species of my improved grate detached from the furnace.

Figure 3 is a side elevation of the grate see-n in Figure 2.

Figure i is a sectional elevation taken on the line 4-4of Figure 2.

Figure 5 is a sectional elevation of one of the air control grate bars corresponding to the structure seen in Figure 4 but Vwith the surrounding parts removed. Y

Figure 6 is a sectional plan View taken o the line 6-6 of Figure 5. Figure 6a is an enlarged fragmentary sectional plan view taken on the line (5a-6a of Figure 4:'. y

Figure 7 is a section taken on therline 7+7 of Figure 5.

Figure 8 is an end view of the bar shown in Figure 5.

Like numerals refer to like parts throughout the drawings.

Describing'in illustration but not-in limitation and referring to the drawings 2-V My grate is particularly designed for the purpose of burning small anthracite coal such as buckwheat, rice or the like.

The grates which have been produced heretofore for the above purpose have generally required artificial draft and so frankly have been admitted to be inoperative without this draft that this requirement is accepted in the art as inevitable. This condition is due to the absence of proper facilities for displacing the ashes vand for adjustably releasing air Within thev body of the bed. 1 Y

In the structure illustrated in Figure 1. I place my grate 10 in a furnace' 11, by insert'- ing pins 12 Athrough downwardly` depending lugs 13 of the furnace into aperturesli in the side bars 15 ofthe grate 10. Y i 1 The method of installation must, of course, be varied according to the type or make of the furnace andthel design ofxits baseV portion; and my. illustration must, therefore, be consideredY as largely diagrammatic.

My grate l-comprises side bars15 and end.- balrs 16, the side bars, 15 being recessed at 17 'to' receive the ends 18 of theend bars pins 19 ywhich project downwardly through openings 20 in the side bars 15 andfastening pins 21 areinserted through the tapered pins 19 to hold the frame together securely.

In the form shown three rakerbarsy22,

23 and 24 are pivoted at 25 infthe side frames 15. These raker arms also have yeach a downwardly projecting earl 26 toV which is secured a common operating lever 27.A

The lever 27, notched at 28 at its outer end, presents three upwardly extending arms 29, 30 and 31 to make pivotal connection at 32 with downwardly projecting ears 26 of the raker bars 22, 23 and 24.

Adjacent the raker bars, and most desirably between them and close enough to interfit with them, I place two vertically movable grate bars 33 and 34 containing a series of holes 50 which when raised or lowered will allow more or less air to circulatethrough the fire bed in the furnace.

These bars 33 and 34 are joined by a bridge or tie bar 35 at their lower ends. At the center of the tie bar 35 a pivoted connection 36 is made with a link 37 which at its outer end 38V is secured to one end 39 of the bell cranklever 40.

The bell crank lever 40 is pivoted at 41 to a fixed downwardly projecting lug 42, preferably integral with the end bar 16. The other end 43 of the bell crank lever is pivoted to and is operated by a movable rod 44 notched at 45 at its outer end so that the rod 44 will retain the bars 33 and 34 at any desired height" adjustments by reason of engagement of the notches in suitable proj ections 46 in the base of the furnace.

It will be clearly seen that by moving the operating lever 27 back and forth the raker bars will oscillate and clear the ashes from the bottom of the fire bed, the .ashes passing through the spaces 47 when the bars are tilted in an angular` position.

The vertically movable bars 33 and 34 tend to break up the clinkers in the bed but find their greatest utility in independently, and in conjunction with disturbing ythe bed, admitting additional air in the disturbed bed area. They are hollow as shown at 48 and air enters at the bottom49, passing from the hollowed portion 48, through apertures 50. These apertures may be inY row formation and it will be obvious that by raising they bar higher into the fire bed as indicated by dot-and-dash lines in Figure 1, air will be released within the bed at `points much nearer the surface of the bed than are the rocker bars. The increased air supply thus secured causes the fire to burn'more rapidly.

-Ina; general way it is intended in Figure 1 to indicate that the sides of the vertically 'movable bars and the sides of the rocker bars -vinterit as by having ribs, fins, teeth or projections on one set extend laterally into thefbody of the other or fit between ribs, fins, teeth or projections of the other. This 'is considered by me not only to be generally desirable but assists in keeping the apertures 50 free from clogging.

`In Figure 2 I have shown one species among a number which would show up in cross-section A.as seen in Figure 1; it being my intention `not to restrict myself to one type of grate that would agree with Figure 1, nor indeed to forms of which Figure 1 would be true, as I consider that my invention is much broader than this and is applicable to a great variety of forms.

In Figure 2 not only the side bars 15 but also the rocker and vertically movable bars are serrated or otherwise formed on the sides so as to have projections or ribs from one interit with projections or ribs on the body lofthe next adjacent structure.

In the villustration the side bars 15 have long and short lugs, projections or fins 5.1 and 52, opposite alternating long and short lugs, projections or fins 53 and 54 are so placed that the long projections from the rocker bars lie opposite the short projections from the fixed end bars and the short projections from the rocker bars lie opposite the long projections from the fixed end bars.

Opposite sides of the rocker bars as shown correspond. The bar 23 is shown as of the same character as regards its lateral projections as the bars 22 and 24 and the-vertically movable bars on opposite sides of bar 23 are provided with lugs, projections or ribs 55 which fit between the long projections 53. v

The end bars 16 are provided further with pairs of lugs 59-59 whichV form guides 60 for the reception of ribs 61 formed on a downwardly extending projection 62 of the vertically movable bars 33 and 34. The ribs 6 1 riding within the grooves 60 keep the bars 33 and 34 in correct alinement during their vertical movement. Y y

Though the broader aspects of my invention do not contemplate that any such special arrangement of adjoining faces (with or without projections) of the bars shall be used the form shown is quite desirable in that it notonly provides for suitable air space during normal -furnace operation but presents `effective staggered spacings 56 and 57 with suitable bed supporting projections breaking up the line of support to advantage. l

In addition to the function already-outlined of breaking up the bed and giving ady types ofgrate and with other types of grate bars, fixed or movable and with a great variety of side surfaces, plain or intertting.

In view of my invention and disclosure variationsV and modilicationsto meet indiico vidual whim or particular need will doubtless become evident to others skilled in the art, to obtain part or all of the beneiits of my invention without copying the structure shown, and I, therefore, claim all such in so far as they fall within the reasonable spirit and scope of my invention.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is l. A grate for burning line coal consisting of a plurality of spaced rocking grate units, a grate frame for supporting the said units, a lever mechanism forrocking the units, crowned, hollow, laterally-apertured, vertically movable grate units,'guides therefor, interitting projections upon the rocking and vertically movable units and a lever Imechanism for imparting vertical movement to the crowned units.

2. A coal burning grate comprising` oscillating grate units and vertically movable grate units, the latter composed of hollow rectangular bodies having a series of openings in the side walls arranged in rows one above the other, a grate frame for supporting the said units, guides integral with the frame and adapted to guide the vertically movable grate units, and lever mechanism for raising them above and lowering-them below the oscillating grate units.

3. A coal burning grate comprising oscillating grate units and vertically movable grate units, lateral projections on each grate unit and adapted to pass between one another, a grate frame for supporting the said units, vertical guides integral withthe frame and adapted to guide the vertically movable units and bearings integral with the grade body adapted to receive the oscillating units.

l. A coal burning grate comprising oscillating grate units, a grateframe for supporting said units, and vertically movable grate units, lateral projections on each of said units interfitting one with the other, manual control for the movement of the oscillating units and separate manual contro-l for the movement of the vertically movable grate units.

5. A coal burning grate comprising oscillating grate units and vertically movable grate units, the latter composed of hollow rectangular bodies having a series of openings in the side walls arranged in rows one above the other, a grate frame for supporting said units, guides integral with the frame and adapted to guide the vertically movable grate units, and lever mechanism` for raising them above and lowering them below the oscillating grate units and means for maintaining the vertically movable units in a. plurality of relative positions with i'espect to the oscillating grate units.

6. A coal burning grate comprising oscillating grate units and vertically movable grate units, the lattercomposed of hollow rectangular Vbodies'having a series of conical open-ings in the side walls arranged in rows oneabove vthe other,a grateframe Vfor supporting said units, guides integral with the body and adapted tofguide the vertical movable grate units, `and lever mechanism: for raising them above and lowering them below the oscillating grate units. Y

7. A coalburning grate comprising oscillating grate units and vertically ,movable grate units, lateral projections on each of said grate units adapted to pass between one another, a grate frame for supporting said units, lateral extensions thereonand adapted to form part of the grate surface, vertical guide lugs thereon adapted to form guideways for the vertically movable grate units and depending lugs thereon adapted to form fulcrum units. Y

8. A coal burning grate comprising oscillating grate units and vertically movable grate units, lateral projections on each of said grate units adapted to pass between one another, a grate frame :tor supporting said units, lateral extensions thereon and adapted to form part of the grate surface, vertical guide lugs thereon adapted to form guideways for the vertically movable grate units and depending lugs thereon adapted to form fulcrum points `l'or the oscillating grate units and lever mechanism for operating the oscillating grate units and separate lever mechanism for operating and maintaining the vertically movable grate units in varying positions with respect to the `oscillating grate Y units.

9. A coal burning grate comprising oscillating grate units and vertically movable' grate units, lateral projections on each of said-grate units adapted to pass between one another, a grate frame forV supporting said units, lateral extensions thereon and adapted to form part of the grate surface, vertical guide lugs thereon adapted to form guideways for the vertically movable grate, thevertically movable grate units comprising a hollow body having a series of openings in the side walls thereof arranged one abovethe other, and projections on the end walls thereof adapted to` fit within the vertical guide lugs on the grate supporting frame..v Y

10. A coal burning grate comprising oscillating grate units and vertically movable grate units, projections on each of said grate sections adapted to pass between one another, a grat-e frame for supporting'said units, vertical guides thereon adapted to guide the vertically movable grate units, depending lugs thereon forming fulcrum points for the oscillating grate units, the

Y vertically movableV grate unitsV comprising hollow rectangular bodies having a series sections.

`of conical openings in the side Walls thereof,

arranged one above the other, and two separate lever mechanisms, one for the simultaneous control of all of the oscillating grate ,units and the other for the simultaneous control of all of the vertically moving grate DAVID A. LITTLE. 

